The invention relates to the design and structure of attachments and their mounting system for firearms. More specifically, the invention relates to tactical attachments mounted to the ammunition magazine tube of long guns and shotguns.
Users of firearms often attach removable devices such as laser sights, flashlights, and other accessories to their weapon. Typically, these attachments require special brackets and mounting systems which are expensive and custom built, each “tactical” device or attachment having its own bracketing or mount. These custom mounts further require alignment with the firearm's point of aim, which can be time consuming to set up and are subject to misalignment if physically bumped during use. Some bracketing interferes with the use of the aiming sights on the weapon which can further hinder use.
If the weapon stores ammunition in a tubular style magazine, tactical attachments may be mounted to the end of the ammunition tube, replacing the stock cap employed by the manufacturer. This mounting method has the advantage of automatic alignment with the weapon's point of aim. Typically, this method has been utilized with pump style shotguns, although it may also be employed with other longs guns having tube magazines such as lever action rifles, for example.
FIG. 1 (prior art) is a side view 100 of a shotgun having an ammunition tube 106. Ammunition tube 106 and pump slide 104 are situated below the barrel 102. Ammunition spring 110 provides the force to feed ammunition (not shown) in the action of the weapon (not shown) for firing. Spring 110 is held within the ammunition tube 106 via cap 112 which is threaded onto ammunition tube 106 via threads 108.
Patent Application Publication US 2010/0277896 A1 by Oehlkers discloses an example of a flashlight threaded on to the ammunition tube of a shotgun. The device combines a flashlight with extended ammunition capacity. One weakness of this approach is that a special flashlight device must be manufactured for every make and model of shotgun or long gun, which can be expensive for owners of multiple weapons. Another weakness is that the ammunition spring 110 is exposed every time the flashlight is removed or replaced with another device, which can lead to the spring launching from the ammunition tube 106 as the attachment is removed. It may also be difficult to re-install the spring if the magazine tube is full of ammunition. This can prove to be disruptive, particularly for peace officers or military personnel who rely on rapid exchange of tactical attachments during moments of high duress. Further, a thread on device 202, such as that shown in FIG. 2, may have the activation switch 204 end up in different locations, depending on the starting position prior to threading the unit 202 on. This can be troubling for military and peace officers who require “hands off” familiarity of their weapon, and can ill afford taking their eyes from the sight picture ahead to find the flashlight on/off switch.
U.S. Pat. No. 5,727,346 to Lazzarini et. al. discloses a device for mounting a flashlight or similar device into a holder attached to (below) slide 104. This system has the disadvantage that the device is mounted to a movable part, and therefore the accuracy (particularly of a laser illumination sight) is questionable. Furthermore, tactical attachments such as door breaching tools or ammunition extension tubes are not compatible with this mounting system.
U.S. Pat. No. 6,565,226 to Cummings discloses flashlight mounting system wherein the flashlight is mounted with a portion of the ammunition tube 106. This system has the disadvantage of consuming ammunition capacity, as a significant portion of the flashlight is mounted within the ammunition tube. It also requires the use of tools for the removal of the flashlight and adapters which would not be suitable for military or police field use. It is also suitable only for the larger gauge shotgun calibers, due the outside diameter requirements of the flashlight.
These and other limitations of the prior art will become apparent to those of skill in the art upon a reading of the following descriptions and a study of the several figures of the drawing.